WO2014067172A1

WO2014067172A1 - Light guide plate and backlight module using same

Info

Publication number: WO2014067172A1
Application number: PCT/CN2012/084261
Authority: WO
Inventors: 张光耀; 熊充
Original assignee: 深圳市华星光电技术有限公司
Priority date: 2012-10-31
Filing date: 2012-11-08
Publication date: 2014-05-08
Also published as: CN102901055A

Abstract

A light guide plate (2), comprising a bottom surface (22), a top surface (24) disposed opposite to the bottom surface (22), and a plurality of side surfaces (26) disposed between the bottom surface (22) and the top surface (24), the plurality of side surfaces (26) including a light incident surface (260); the bottom surface (22) is provided with a plurality of grid points (220) thereon having right triangle cross sections; the grid points (220) are formed by recessing the bottom surface (22) of the light guide plate toward the top surface (24); each grid point (220) has an inclined surface (222) facing the light incident surface (260); the inclined surface (222) is disposed gradually sloping away from the light incident surface (260) from the bottom surface (22) to the top. Also disclosed is a backlight module using the light guide plate (2). The light guide plate (2) and the backlight module using the light guide plate (2) are provided with recessed right-triangle-shaped grid points (220) on the bottom surface (22) of the light guide plate (2), so that the light enters the light guide plate (2) through the light incident surface (260) of the light guide plate (2), is then reflected by the grid points (220), and exits from the top surface (24) of the light guide plate (2). In this manner, most of the light energy is concentrated in the normal direction of the light guide plate (2), thus effectively improving the light utilization.

Description

Light guide plate and backlight module using the same

The present invention relates to the field of liquid crystal display, and in particular to a light guide plate and a backlight module using the same. Background technique

Liquid crystal display (LCD) has many advantages such as thin body, power saving, and no radiation, and has been widely used. Most of the liquid crystal display devices on the market are backlight type liquid crystal displays, which include a liquid crystal panel and a backlight module. The working principle of the liquid crystal panel is to place liquid crystal molecules in two parallel glass. There are many vertical and horizontal small wires between the two glass plates. The liquid crystal molecules are controlled to change direction by energization or not, and the light of the backlight module is refracted. Picture. Since the liquid crystal panel itself does not emit light, it is necessary to display the image normally by the light source provided by the backlight module. Therefore, the backlight module becomes one of the key components of the liquid crystal display device. The backlight module is divided into a side-in type backlight module and a direct-type backlight module according to different incident positions of the light source. In the direct type backlight module, a light source such as a CCFL (Cold Cathode Fluorescent Lamp) or an LED (Light Emitting Diode) is disposed behind the liquid crystal panel, and a surface light source is directly formed and supplied to the liquid crystal panel. The side-lit backlight module is provided with an LED light bar disposed on the edge of the back panel behind the liquid crystal panel, and the light emitted by the LED strip enters the light guide plate from the light incident surface of the light guide plate, and is reflected and After being diffused, it is emitted from the light-emitting surface of the light guide plate to form a surface light source to be supplied to the liquid crystal panel.

In order to increase the illumination and the light intensity, generally, the dots are arranged on the bottom surface of the light guide plate, and the functions of the dots are to change the direction of light propagation. At present, the manufacturing methods of the dots mainly include ink printing, mechanical engraving, chemical etching, mold injection molding, etc. .

As shown in FIGS. 1 and 2, the reflective surface 302 of the mesh point 300 of the bottom surface 102 of the conventional light guide plate 100 is parallel to the bottom surface 102 of the light guide plate 100. The light source 500 is located at one side of the light guide plate 100, and the emitted light is incident on the mesh point. Total reflection occurs on the reflecting surface 302 of the 300, and then exits from the light emitting surface 304 of the light guide plate 100. The spatial distribution of the emitted light is not symmetric with the normal direction of the light guide plate 100. The direction of the maximum energy of the light is not the normal direction of the light guide plate 100, but a direction with a larger angle β from the normal direction, resulting in light. The utilization rate is small, and a diffusion sheet is added to the light guide plate 100 to correct the direction of the emitted light, and the direction of the maximum light energy is parallel to the normal direction of the light guide plate 100. Summary of the invention

It is an object of the present invention to provide a light guide plate having a bottom dot which allows most of the energy of the outgoing light to be concentrated in the normal direction of the light guide plate, thereby effectively improving light utilization.

Another object of the present invention is to provide a backlight module which has a simple structure, high light intensity, and good illumination.

In order to achieve the above object, the present invention provides a light guide plate, comprising: a bottom surface, a top surface disposed opposite to the bottom surface; and a plurality of side surfaces disposed between the bottom surface and the top surface, wherein the plurality of side surfaces include a light incident surface The bottom surface is provided with a plurality of mesh points having a right-angled triangular cross section. The mesh dots are formed by recessing the bottom surface of the light guide plate toward the top surface. The mesh dots have a sloped surface facing the light incident surface, and the inclined surface is gradually disposed from the bottom surface toward the light incident surface.

The slope of the dot forms an angle with the bottom surface of the light guide plate, and the angle of the angle is between 40° and 50 degrees. between.

The dots are formed on the bottom surface of the light guide plate by embossing or engraving.

The dot has a straight face away from the light incident surface, the straight face being perpendicular to the bottom surface.

The present invention further provides a backlight module, including: a back plate, a light guide plate disposed in the back plate, and a backlight disposed in the back plate, wherein the light guide plate includes a bottom surface, a top surface disposed opposite to the bottom surface, and a plurality of sides between the bottom surface and the top surface, wherein the plurality of side surfaces comprise a light incident surface, wherein the bottom surface is provided with a plurality of mesh points having a right-angled triangular cross section, wherein the mesh dots are formed by recessing the bottom surface of the light guide plate toward the top surface, The dot has a slope facing the light entrance surface, and the slope is disposed from the bottom surface upwardly away from the light incident surface.

The backplane includes a bottom plate and a plurality of side plates connected to the bottom plate, wherein the backlight is mounted on the side plate of the back plate corresponding to the light incident surface of the light guide plate; and a heat sink is further disposed between the backlight and the side plate. The backlight is attached to the heat sink by a heat-dissipating adhesive, and the heat sink is fixedly mounted on the side plate by screwing or gluing; the backlight is a linear LED light bar. Optical film set. , — ' , , , , , '

The present invention also provides a light guide plate, comprising: a bottom surface, a top surface disposed opposite to the bottom surface; and a plurality of side surfaces disposed between the bottom surface and the top surface, wherein the plurality of side surfaces include a light incident surface, wherein the bottom surface is provided There are a plurality of dots having a right-angled triangle, and the dots are recessed from the bottom surface of the light guide plate toward the top surface. Forming, the dot has a slope facing the light entrance surface, and the slope is gradually moved away from the bottom surface by the bottom surface;

Wherein the inclined surface of the dot forms an angle with the bottom surface of the light guide plate, and the angle of the angle is between

Between 40° and 50°;

The dot is formed on the bottom surface of the light guide plate by embossing or engraving; wherein the dot has a straight surface away from the light incident surface, and the straight surface is perpendicular to the bottom surface.

Advantageous Effects of the Invention: The light guide plate of the present invention and the backlight module using the light guide plate have a right-angled triangular HJ trap point on the bottom surface of the light guide plate, and the light emitted by the backlight is incident on the light guide plate from the light incident surface of the light guide plate. Inside, the reflection of the dot is emitted from the light exit surface of the light guide plate, and the energy of the light is mostly concentrated in the normal direction of the light guide plate, thereby effectively improving the light utilization efficiency.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings. DRAWINGS

The technical solutions and other advantageous effects of the present invention will be apparent from the following detailed description of embodiments of the invention.

In the drawings,

1 is a schematic diagram of light propagation of a conventional light guide plate;

2 is a distribution diagram of an outgoing light energy of a conventional light guide plate;

3 is a schematic diagram of light propagation of a light guide plate of the present invention;

4 is a light distribution diagram of an outgoing light of a light guide plate of the present invention;

FIG. 5 is a schematic structural view of a backlight module of the present invention. detailed description

In order to further clarify the technical means and effects of the present invention, the following detailed description will be made in conjunction with the preferred embodiments of the invention and the accompanying drawings.

Referring to FIG. 3 and FIG. 4 , the present invention provides a light guide plate 2 including: a bottom surface 22 , a top surface 24 disposed opposite the bottom surface 22 , and a plurality of side surfaces 26 disposed between the bottom surface 22 and the top surface 24 , the number A side surface 26 includes a light incident surface 260.

The bottom surface 22 is provided with a plurality of mesh dots 220 having a right-angled triangular cross section. The mesh dots are formed by the bottom surface 22 of the light guide plate 2 toward the top surface 24. Preferably, the mesh dots 220 are formed on the light guide plate by embossing or engraving. 2 on the bottom surface 22.

The dot 220 has a slope 222 facing the light incident surface 260, and the slope 222 is formed by the bottom surface. 22 is gradually disposed away from the light incident surface 260. The inclined surface 222 of the mesh point 220 forms an angle Θ with the bottom surface 22 of the light guide plate 2. Preferably, the angle Θ angle is between 40° and 50°.

The dot 220 also has a straight face 224 that is remote from the light incident surface 260, the straight face 224 being perpendicular to the bottom face 22.

When the light enters the light guide plate 2 from the light incident surface 260, the reflection from the inclined surface 222 of the mesh point 220 is emitted from the top surface 24 of the light guide plate 2, so that the energy of the light is mostly concentrated in the normal direction of the light guide plate 2, thereby effectively improving Light utilization.

4 is a distribution diagram of the emitted light energy of the light guide plate of the present invention. As can be seen from FIG. 4, most of the energy of the light emitted by the light guide plate 2 of the present invention is concentrated in the normal direction of the light guide plate 2, thereby effectively improving the light. Utilization rate.

Referring to FIG. 3 to FIG. 5 , the present invention further provides a backlight module, including: a back plate 4, a light guide plate 2 disposed in the back plate 4, and a backlight 6 disposed in the back plate 4.

The light guide plate 2 includes a bottom surface 22, a top surface 24 disposed opposite the bottom surface 22, and a plurality of side surfaces 26 disposed between the bottom surface 22 and the top surface 24. The plurality of side surfaces 26 include a light incident surface 260.

The bottom surface 22 is provided with a plurality of mesh dots 220 having a right-angled triangular cross section. The mesh dots 220 are formed by the bottom surface 22 of the light guide plate 2 toward the top surface 24. Preferably, the mesh dots 220 are formed by embossing or engraving. On the bottom surface 22 of the light panel 2.

The mesh point 220 has a slope 222 facing the light incident surface 260. The slope surface 222 is gradually disposed away from the light incident surface 260 by the bottom surface 22. The slope 222 of the mesh point 220 forms an angle with the bottom surface 22 of the light guide plate 2, Preferably, the angle Θ angle is between 40° and 50°.

The backlight 6 is a linear LED strip, and the light emitted from the light-incident surface 260 of the light guide plate 2 enters the light guide plate 2, and is reflected by the top surface 24 of the light guide plate 2 through the reflection of the inclined surface 222 of the mesh point 220, so that the light is emitted. Most of the energy is concentrated in the normal direction of the light guide plate 2, thereby effectively improving the light utilization efficiency.

The backplane 4 includes a bottom plate 42 and a plurality of side plates 44 connected to the bottom plate 42. The backlight 6 is mounted on the side plate 44 of the back plate 4 corresponding to the light incident surface 260 of the light guide plate 2. Preferably, the backlight A heat sink 64 is further disposed between the source 6 and the side plate 44. The backlight 6 is attached to the heat sink 64 by a heat dissipating adhesive (not shown). The heat sink 64 is fixed by screw locking or gluing. Mounted on the side panel 44 of the backboard 4.

It is to be noted that the backlight module further includes a reflective sheet 8 disposed between the bottom plate 42 of the back plate 4 and the bottom surface 22 of the light guide plate 2, and an optical film set 10 disposed on the top surface 24 of the light guide plate 2, and the backlight The light emitted by the source 6 is directly or reflected by the reflection sheet 8 and enters the light guide plate 2 to provide light. Take a uniform surface light source.

In summary, the light guide plate of the present invention and the backlight module using the light guide plate are provided with a right-angled triangular HJ trap point on the bottom surface of the light guide plate, and the light emitted by the backlight is incident on the light guide plate through the light incident surface of the light guide plate. The reflection from the dot is emitted from the light-emitting surface of the light guide plate, and the energy of the light is mostly concentrated in the normal direction of the light guide plate, thereby effectively improving the light utilization efficiency.

In the above, various other changes and modifications can be made in accordance with the technical solutions and technical concept of the present invention, and all such changes and modifications are within the scope of the claims of the present invention. .

Claims

Rights request

1. A light guide plate, including: a bottom surface, a top surface arranged opposite to the bottom surface, and several side surfaces located between the bottom surface and the top surface. The several side surfaces include a light incident surface, and the bottom surface is provided with several The cross-section is a right-angled triangle mesh point, which is formed by the bottom surface of the light guide plate being recessed toward the top surface. The mesh point has an inclined surface toward the light incident surface, and the inclined surface is gradually arranged away from the light incident surface from the bottom surface upward.

2. The light guide plate according to claim 1, wherein the inclined surface of the dots and the bottom surface of the light guide plate form an included angle, and the included angle is between 40° and 50°.

3. The light guide plate according to claim 1, wherein the dots are formed on the bottom surface of the light guide plate by imprinting or engraving.

4. The light guide plate according to claim 1, wherein the dot has a straight surface away from the light incident surface, and the straight surface is perpendicular to the bottom surface.

5. A backlight module, including: a backplane, a light guide plate disposed in the backplane, and a backlight source disposed in the backplane. The light guide plate includes a bottom surface, a top surface disposed opposite to the bottom surface, and a light guide plate disposed between the bottom surface and the backlight module. There are several side surfaces between the top surfaces, including a light incident surface. The bottom surface is provided with a plurality of mesh points with right-angled triangle cross-sections. These mesh points are formed by the bottom surface of the light guide plate being recessed toward the top surface. The mesh points are It has an inclined surface facing the light incident surface, and the inclined surface is gradually arranged away from the light incident surface from the bottom surface upward.

6. The backlight module of claim 5, wherein the inclined surface of the dots and the bottom surface of the light guide plate form an included angle, and the included angle is between 40° and 50°.

7. The backlight module of claim 5, wherein the dots are formed on the bottom surface of the light guide plate by imprinting or engraving.

8. The backlight module of claim 5, wherein the dot has a straight surface away from the light incident surface, and the straight surface is perpendicular to the bottom surface.

9. The backlight module of claim 5, wherein the back panel includes a bottom panel and several side panels connected to the bottom panel, and the backlight source is installed on the side panel of the back panel corresponding to the light incident surface of the light guide plate; There is also a heat sink between the backlight and the side panel, the backlight is attached to the heat sink through heat dissipation glue, and the heat sink is fixedly installed on the side panel through screw locking or gluing; the backlight The source is a linear LED strip.

10. The backlight module of claim 9, further comprising a reflective sheet disposed between the bottom surface of the backplane and the bottom surface of the light guide plate and an optical film set disposed on the top surface of the light guide plate.

11. A light guide plate, including: a bottom surface, a top surface arranged opposite to the bottom surface, and several side surfaces located between the bottom surface and the top surface. The several side surfaces include a light incident surface, and the bottom surface is provided with several The cross-section is a right-angled triangle mesh point, which is formed by the bottom surface of the light guide plate being recessed toward the top surface. The mesh point has an inclined surface toward the light incident surface, and the inclined surface is gradually arranged away from the light incident surface from the bottom surface upward;

Wherein, the slope of the dots and the bottom surface of the light guide plate form an included angle, and the included angle is between

Between 40° ~ 50°;

Wherein, the dots are formed on the bottom surface of the light guide plate by imprinting or engraving; wherein the dots have a straight surface away from the light incident surface, and the straight surface is perpendicular to the bottom surface.